I know protecting images is far from foolproof. However, clients ask for it, so I have Javascript on a site which is designed to prevent right-click saving/downloading.
It appears that Reader View ignores both the Javascript and the site's CSS. I tried to add {display:none} based on a rule .moz-reader-content (Firefox). I've assumed this is the case in all browsers.
Searching hasn't turned up a means of detecting reader view either.
Does anyone have any suggestions or know of a solution for this problem?
As you know there are no full-proof solutions. No matter what you do, if it's visible it can be copied. (With a screenshot as a last resort).
With that being said, a simple and surprisingly effective solution is just to overlay each image a transparent .png file.
<div id="imagecontainer" style="position:relative;">
<img src="yourimage.png" style="position:absolute;top:0px;left:0px;">
<img src="transparent-overlay.png" style="position:absolute;top:0px;left:0px;">
</div>
Right-clicking on the image, would then click on the overlay and not the image itself. (Of course, you'll want to give the overlay a less obvious name).
Additionally, you should watermark the image itself.
For getting around Reader View issues (I'm not sure which Reader View you're talking about btw), you could try using javascript to actually fill the images themselves. (Assuming your reader view doesn't permit js).
eg:
var i = document.createElement('img');
var o = document.createElement('img');
i.src = 'yourimage.png';
o.src = 'transparent-overlay.png';
document.getElementById('imagecontainer').appendChild(i);
document.getElementById('imagecontainer').appendChild(o);
In the latter js example you'd also need to set your css styles to absolute position the two images within #imagecontainer.
Related
In my hybrid Android app I use inline SVG to display images that are large (of the order of 2Mb) and complex (several hundred SVG elements per image). When I need to change the image I do the following
var puzzle = document.createElementNS(SVGNS,'svg'),
kutu = document.getElementById('kutu');
puzzle.id = 'puzzle';
puzzle.setAttribute('preserveAspectRatio','none');
puzzle.setAttribute('width','100vw');
puzzle.setAttribute('height','85.5vh');
puzzle.setAttribute('xmlns',SVGNS);
puzzle.setAttribute('xmlns:xlink',XLINK);
puzzle.setAttribute('fill-rule','evenodd');
puzzle.setAttribute('clip-rule','evenodd');
puzzle.setAttribute('stroke-linejoin','round');
puzzle.setAttribute('stroke-miterlimit','1.414');
puzzle.setAttribute('viewBox','0 0 1600 770');
puzzle.innerHTML = SVG;
//SVG here is the SVG image content shorn off the outer <svg>..</svg>
if (0 < kutu.children.length) kutu.children[0].remove();
//remove old image, iff any
kutu.appendChild(puzzle);
//append the new image
While this is working the process of displaying the new image is slow. I suspect it is because of the innerHTML assignment above. Recreating through a sequence of createElementNS, puzzle.àppendChild would require me to first parse the incoming raw SVG content etc. Is that the way to go or would there be a faster way to display the content.
Once again for clarity - SVG here is the content of the new SVG image to be displayed shorn of its outer <svg>...</svg> wrrapper.
Just a side note it would probably be better to use setAttributeNS in place of setAttribute for consistency purpose since createElementNS is used, though it might not make a difference in speeding up the SVG image change.
In the case of a native app, a tool like the Android Profiler if using Android Studio 3.0 and higher can be used to analyze performance bottleneck. However since your app is a hybrid app, some sort of performance profiler that's applicable to the hybrid app (Whether it's Ionic or Cordova, etc.) can help to pinpoint where your performance bottleneck is.
Since your app is a hybrid, without knowing the resource capacity of your android app session, the guess is it seems to be a possible cause that it calls something like .setAttribute to set session-level attributes on the fly during the change of the image and the session resource might not be enough, and also the DOM has to perform .innerHTML and appendChild, which are dynamic operations. DOM manipulation is known to be slow.
Conversion of attributes of all the SVGs and store the result in some sort of storage or cache, and when needed, call it from the persistent storage or cache might be helpful.
Or consider using AngularJS to do the SVG change beforehand and preload the SVG images, refer to easily preload images in your Angular app. Here is another similar code to yours except it's using AngularJS to add SVG for starters.
Another simpler way, without changing your code, if you could minify the incoming SVGs beforehand, is to use SVG Optimizer or SVGO, a node.js open source project to compress your SVGs. Quoted from the SVGO link it says:
"SVG files, especially those exported from various editors, usually contain a lot of redundant and useless information. This can include editor metadata, comments, hidden elements, default or non-optimal values and other stuff that can be safely removed or converted without affecting the SVG rendering result." Although the performance gain might not be obvious going this route.
I have a big SVG document here, containing a map of all the quests in a certain online game. Each quest node is inside a SVG <a> element, linking to a distinct named anchor in a big HTML document that loads in another tab, containing further details about that particular quest. This works exactly as desired in desktop Safari, and I'd expect it to work just as well in any browser that supports SVG at all since I'm using only the most basic form of linking, but it fails badly on Mobile Safari (iOS 6) - which is my single most important browser target, considering that the game in question is for the iPad. It only scrolls to the correct anchor on the initial load of the HTML page; clicking a different quest in the SVG tab will cause a switch to the HTML tab, and the hash (fragment ID) in the address bar changes, but the page doesn't auto-scroll.
This appears to be a known limitation in Mobile Safari - hash-only changes in the URL apparently used to force a page reload, and that got over-fixed such that nothing gets triggered at all now. The fixes I've found online all seem to be applicable only in cases where the URL change is being generated programatically, from within the same document, rather than static links from a different document.
Further details:
I've tried doing the named anchors in both the old <a name="..."> form, and the newer <h1 id="..."> form. No difference.
I've tried adding an onhashchange handler, to force the scrolling to take place, but the handler isn't being called at all (verified by putting an alert() in it).
I could presumably fix the problem by having each quest's details in a separate HTML file, but that would severely affect usability - with all the details in a single file, you can use your browser's Find feature to search through them all at once. (Also, deploying 1006 files to my web hosting after each update would be a bit of a pain...)
Anybody have an idea for a work-around?
I am trying to create an interactive map where users can click on different provinces in the map to get info specific to that province.
Example:
archived: http://www.todospelaeducacao.org.br/
archived: http://code.google.com/p/svg2imap/
So far I've only found solutions that have limited functionality. I've only really searched for this using an SVG file, but I would be open to other file types if it is possible.
If anyone knows of a fully functioning way to do this (jQuery plug-in, PHP script, vector images) or a tutorial on how to do it manually please do share.
jQuery plugin for decorating image maps (highlights, select areas, tooltips):
http://www.outsharked.com/imagemapster/
Disclosure: I wrote it.
Sounds like you want a simple imagemap, I'd recommend to not make it more complex than it needs to be. Here's an article on how to improve imagemaps with svg. It's very easy to do clickable regions in svg itself, just add some <a> elements around the shapes you want to have clickable.
A couple of options if you need something more advanced:
http://jqvmap.com/
http://jvectormap.com/
http://polymaps.org/
I think it's better to divide my answer to 2 parts:
A-Create everything from scratch (using SVG, JavaScript, and HTML5):
Create a new HTML5 page
Create a new SVG file, each clickable area (province) should be a separate SVG Polygon in your SVG file,
(I'm using Adobe Illustrator for creating SVG files but you can find many alternative software products too, for example Inkscape)
Add mouseover and click events to your polygons one by one
<polygon points="200,10 250,190 160,210" style="fill:lime;stroke:purple;stroke-width:1"
onmouseover="mouseOverHandler(evt)"
onclick="clickHandler(evt)" />
Add a handler for each event in your JavaScript code and add your desired code to the handler
function mouseOverHandler(evt) {};
function clickHandler(evt) {};
Add the SVG file to your HTML page (I prefer inline SVG but you can use linked SVG file too)
Upload the files to your server
B-Use a software like FLDraw Interactive Image Creator (only if you have a map image and want to make it interactive):
Create an empty project and choose your map image as your base image when creating the new project
Add a Polygon element (from the Shape menu) for each province
For each polygon double click it to open the Properties window where you can choose an event type for mouse-over and click,
also change the shape opacity to 0 to make it invisible
Save your project and Publish it to HTML5, FLDraw will create a new folder that contains all of the required files for your project that you can upload to your server.
Option (A) is very good if you are programmer or you have someone to create the required code and SVG file for you,
Option (B) is good if you don't want to hire someone or spend your own time for creating everything from scratch
You have some other options too, for example using HTML5 Canvas instead of SVG, but it's not very easy to create a Zoomable map using HTML5 Canvas,
maybe there are some other ways too that I'm not aware of.
Just in case anyone will search for it - I used it on several sites, always the customization and RD possibilities were a perfect fit for what I needed. Simple and it is free to use:
Clickable CSS Maps
One note for more scripts on a site: I had some annoying problems with getting to work a map (that worked as a graphic menu) in Drupal 7. There where many other script used, and after handling them, I got stuck with the map - it still didn't work, although the jquery.cssmap.js, CSS (both local) and the script in the where in the right place. Firebug showed me an error and I suddenly eureka - a simple oversight, I left the script code as it was in the example and there was a conflict. Just change the front function "$" to "jQuery" (or other handler) and it works perfect. :]
Here's what I ment (of course you can put it before instead of the ):
<script type="text/javascript">
jQuery(function($){
$('#map-country').cssMap({'size' : 810});
});
</script>
Go to SVG to Script
with your SVG the default output is the map in SVG
Code which adds events is also added but is easily identified and can be altered as required.
I have been using makeaclickablemap for my province maps for some time now and it turned out to be a really good fit.
I had the same requirements and finally this Map converter worked for me. It is the best plugin for any map generation.
Here is another image map plugin I wrote to enhance image maps: https://github.com/gestixi/pictarea
It makes it easy to highlight all the area and let you specify different styles depending on the state of the zone: normal, hover, active, disable.
You can also specify how many zones can be selected at the same time.
The following code may help you:
$("#svgEuropa [id='stallwanger.it.dev_shape_DEU']").on("click",function(){
alert($(this).attr("id"));
});
Source
You have quite a few options for this:
1 - If you can find an SVG file for the map you want, you can use something like RaphaelJS or SnapSVG to add click listeners for your states/regions, this solution is the most customizable...
2 - You can use dedicated tools such as clickablemapbuilder (free) or makeaclickablemap (i think free also).
[disclaimer] Im the author of clickablemapbuilder.com :)
<script type="text/javascript">
jQuery(function($){
$('#map-country').cssMap({'size' : 810});
});
</script>
strong text
Suppose I want the browser to load an image right on the first connection it makes to my website. How do I do that, considering that by default the image loads later on when it's actually called for?
Also, after the whole page finishes loading, suppose I want to load more objects (say images) that aren't required yet but are just for buffer. How do I do that? Help me people, I've been at it for quite a long time.
I'm somewhat successful with the first problem by adding a script tag while actually calling an image at the beginning of my index.php's html head part which goes like:
<script src="http://www.mysite.com/my/image/url.png"></script>
But this I realize is bad scripting.
As for "Why would you want to do that?", it's for educational purposes and also because when someone visits my site, I need to load and display certain things before other things get loaded.
For preloading you probably could start with
<body onLoad="Preload('image1.jpg', 'image.gif', 'image.png', ...)">
And preload is a JavaScript function which adds each of the array of images to DOM like
document.imageArray[i].src = args[i];
I am creating an ASP.NET web application. In one of my webpages (an ASCX control) I am placing a fusion chart inside a <div> tag. I want to provide an option for the client to download this fusion chart.
Is there any way that I can download
the fusion chart present in the Div
tag, as an image (Using javascript
because the div tag is a client side
control).
The request is that my client could save this fusion chart present in the <div> tag as an image when he visits the webpage.
The target browser is IE.
Please help me.
I can confirm that it is not possible to 'Export the chart as image' when using FusionCharts Free. However, as mentioned by Larsenal, you will be able to use FusionCharts v3.2.1 and it's updated JavaScript API to export pure JavaScript charts to JPEG, PNG, PDF, SVG formats.
Ref.- http://www.fusioncharts.com/docs/?ECPureJS.html
Furthermore, you may even export your Flash charts, if required, in a similar manner. DO check out the link below for a more detailed account of the same.
Ref.- http://www.fusioncharts.com/docs/?ECOverview.html
Hope this helps.
It is currently not possible to generate an image from a section of a webpage with JavaScript. Quoting myself from another question:
Firefox added something similar to
this to their canvas implementation.
You can find
CanvasRenderingContext2D.drawWindow()
documented in their wiki. It is
restricted to being used by plugins,
for security purposes, and isn't
supported by any other browsers.
There is
talk
of adding support to other browsers,
and perhaps removing some of the
security restrictions, but that is
probably a long way off. For now,
there isn't a good JavaScript solution
to your problem.
Sorry, there's no way to do it with Javascript.
I don't know about the Fusion controls, but some graphing libraries include a way to render to an image or PDF. Start looking there, not Javascript.
Update: FusionCharts claims to have the ability to export to JPG, PNG, PDF and CSV. Start with this page about exporting pure JS charts in their documentation.